The Cubs saw a brief preview of life in the postseason on June 14 in Washington when they took a 3–2 lead into the eighth inning against the Nationals. Bryce Harper was the leadoff batter. For that key at-bat—keeping the National League's reigning MVP in check and protecting a one-run lead with six outs to go—the best option for Chicago manager Joe Maddon was Travis Wood.

Now, that's nothing against Wood; he’s a fine pitcher, and he does well against lefthanders, holding them to a .606 OPS in his seven MLB seasons. But his role never has been consistently to get out hitters late in the game.

In this case, Wood walked Harper on six pitches. The leadoff walk soon became the tying run. The Cubs would score the go-ahead run in the top of the ninth and win 4–3, but the eighth-inning shivers caused by watching Wood walk Harper remained.

Chicago has waited 108 years to win the World Series. This year, the Cubs have the best team in baseball. The Greatest Championship in Sports may never have appeared as close to reality as it does this year. But Chicago had one obvious flaw, and there was no way Cubs president Theo Epstein and general manager Jed Hoyer were letting their team enter October with it: Who could they trust this October to get the franchise's biggest outs in more than a century?

The answer is not Hector Rondon, the former Rule 5 pick who has been the team's closer the past three seasons and is good enough in most circumstances. It is not Mike Montgomery, the talented lefthander Chicago just obtained from Seattle who has never secured a big out in his major league life. And it is not the wily, if limited, Wood.

The answer was the Usain Bolt of baseball: Aroldis Chapman, a physical freak who throws a baseball demonstrably faster than the rest of humankind. During one game last week, Chapman was clocked at 105 mph.

On Monday, Chicago obtained Chapman in a trade from the Yankees for a package of players that includes just two significant ones from Chicago’s side: minor league infield prospect Gleyber Torres and major league righthander Adam Warren. Also part of the deal are Double A outfielder Billy McKinney and Class A outfielder Rashad Crawford.

Player development people may point out the pain the Yankees extracted from Chicago. McKinney, who turns 22 next month, was a first-round draft pick three years ago. Torres was ranked no worse than No. 41 by the three major projection lists before this season started. Warren, who will be 29 next month, was a valuable swingman for New York's wild-card-winning team last year before being traded to the Cubs to get second baseman Starlin Castro last December. So it appears the Cubs gave up a higher price to rent Chapman, a free agent to be, than the Orioles gave up two years ago to rent reliever Andrew Miller from Boston, when they surrendered starting pitcher Eduardo Rodriguez—and the Yankees flipped Chapman after just 31 1/3 innings at a much higher price than what they paid the poor Reds to acquire him before the season started.

But let’s cool the rhetoric on Torres just a bit. He’s not the next Francisco Lindor. It’s most likely he is a second baseman, not a shortstop, in the Martin Prado mold. There's nothing wrong with that; it just means Torres does not project to be a high impact player. McKinney, meanwhile, has yet to reach Triple A, has a .772 OPS in four minor league seasons and is batting .252 with one home run at Double A this year.

Besides, life in the prospect world has become such an overhyped soup of rankings, lists and dreamy projections that sometimes we lose sight of the fact that the goal of Major League Baseball is to win the World Series, not to have the No. 1 ranked farm system. No one commissions a gaudy diamond-encrusted ring for the latter.

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The Cubs built a system strong enough to use it to get the missing pieces of a possible championship. They can now trust the final six outs—or more—to Rondon and Chapman, two guys who this year have combined to allow just 42 hits and struck out 92 batters in 68 1/3 innings.

This is the emphasis of postmodern baseball: Don’t just get outs late—don’t even let the ball be hit into play, which could lead to bad things happening.

The other day I was speaking with Giants executive vice president Brian Sabean about relief pitching. His teams won three world championships in five years from 2010 to '14 with the help of a finesse, matchup bullpen managed brilliantly by Bruce Bochy. But as we spoke, San Francisco was last in the league in strikeout rate by relievers, and Sabean and GM Bobby Evans were scouring the trade market for veteran relievers with swing-and-miss stuff.

“The game has changed in a short period of time,” Sabean said. “Now everybody wants power arms that keep the ball out of play late in the game. And a lot of teams have two, three or four of them.”

Over the past two postseasons, the Kansas City bullpen went 15–1 with 11 saves, 12 holds and 159 strikeouts in 127 innings (11.3 per nine innings), helping the Royals reach Game 7 of the World Series one season and win the championship the next. The value of power relievers is enhanced in the postseason because of the urgency of the games and the days off in between. Managers can use their winning pieces more often and for more outs. Kansas City closer Wade Davis, for instance, went longer than one inning more times in the postseason (six) than he did in the regular season (four) during the past two years.

In Chapman, Chicago now has a similar weapon, and he loves the work. While Yankees manager Joe Girardi does not like using the same relievers on three straight days, Chapman told him he was fine about it and even likes it. Maddon can cover as many as the last seven to nine outs with Rondon and Chapman. It’s not a matchup bullpen; it’s a lights-out bullpen.

The Cubs began their quest for a late-inning solution by asking for Davis from the Royals and Miller from the Yankees. In both cases the clubs asked Chicago for catcher/outfielder Kyle Schwarber in return. In both cases the Cubs immediately told them Schwarber, a 23-year-old power hitter, was untouchable. Having teams ask for a player who is out for the year with a knee injury and having his team shut down any such talk immediately is a strong indication about the ceiling for Schwarber, who looks like the next big impact hitter in the game as well as a high-character building block.

As for the Yankees, they are in the early stages of rebuilding around young position players, such as Castro and shortstop Didi Gregorius from the parent club and minor leaguers like Torres, first baseman Greg Bird, outfielder Aaron Judge, shortstop Jorge Mateo and catcher Gary Sanchez. (A reminder to player development fans that such dreams are fungible; just a few years ago, the Cubs were touting the likes of Castro, Brett Jackson and Josh Vitters, none of whom are with the team this year.) But it’s a start. New York now buys another week before the trade deadline to see if it should sell off more parts, such as outfielder Carlos Beltran

October is a minefield of unseen dangers. Chicago can get tripped up by the power starting pitching of the Nationals or, as happened last year, the Mets, or by the veteran savvy and contact-hitting of the Giants, or simply by a hotter team. But the Cubs have certainly done their part to ensure they will be as prepared as possible.

Just four years ago, in the first season under the architectural firm of Epstein & Hoyer, Chicago lost 101 games and used 53 players. Only two remain: Wood and first baseman Anthony Rizzo. A four-year complete rebuild—accomplished mostly through trades and free agents, not the draft—now has reached its critical mass. The finishing piece, either for the last out or the last century, is Chapman.

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